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Starting with the flood of questions! :grin: I would like the advice of the forum on what to do with the drivetrain in my 73' coupe. I have 2 options I am considering. I would really prefer an automatic trans with either, so that has to be a consideration. I don't mind having to do a little fabrication to mounts and such, but don't want to re-engineer the car to make it work. Without further ado,

 

Option # 1 - Old school

 

EA71 with the 1400 "4 port" heads. Searching around, it seems this is possible with some work to the head water jackets and a cam swap. the questions with this are,

 

-Are the "4 port" heads that superior to the "2 port" heads?

-Will the EA63 cam fit in the EA71 block?

-Are there automatics that will fit this engine/chassis combo? Are they direct bolt in or are mods needed?

 

Reason: To KISS and have it appear original while increasing the power output and possibly reliability. Seems the wet liner 1400 can develop head gasket issues?

 

 

Option #2 - New tech

 

EJ18/22, maybe turbo

 

Questions,

 

-Supposedly this is almost a direct drop in, engine wise?

-Transmission. Will a EJ automatic fit in the coupe? I guess my main concern would be location of the output shaft and CV compatibility. If the EJ auto is not feasible, will the adapter plate work with an EA automatic? If I had my druthers, I would like the auto to be 4 speed. This would obviously be FWD only.

 

Reason: Modern performance and the driveability of fuel injection. From what I read, the small EJ's are pretty rugged engines.

 

So, what do you all think?

 

Mark

Edited by Datsunrides
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For as rare as the car is, I say old school mostly stock option.

It's nicer to see a stock restored car than a modified restored car (ask Bucky92)

I say hot rod tune the engine and eek as much HP as you can out of it without

destroying it, and keep the stock configuration.

You should be able to find a 3AT that will work with an EA71.

They are out there.

 

Twitch

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For as rare as the car is, I say old school mostly stock option.

It's nicer to see a stock restored car than a modified restored car (ask Bucky92)

I say hot rod tune the engine and eek as much HP as you can out of it without

destroying it, and keep the stock configuration.

You should be able to find a 3AT that will work with an EA71.

They are out there.

 

Twitch

 

I am the type that likes to modernize where applicable. I am leaning toward the EJ engine *BUT* I also do not wish to make irreversable changes, should I or a future owner want to return to original. Should the EJ require substantial modifications, my choice just became easier. Oh, and automatic due to the fact my wife likes to occasionally drive my classics and won't drive a stick! :rolleyes:

 

Mark

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Theres a 3rd option if you are really considering an automatic...

 

EA81 and EA82 cars had FWD automatic gearboxes (3-speeds I believe) they weren't that great, but they would bolt-in easier than an EJ FWD automatic transmission.

 

But really, if you want reliability and automatic, i'd probably go with an EJ drive train.

 

You have limited options if you want to bolt a Automatic transmission to the 1400 due to the location of the starter, but there were a few (very few) late 70's and early 80's models that offered automatics with the FWD drivetrain.

Edited by Kostamojen
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Is a EJ18 wider than a EJ15?

 

I know that if you where to fit in a Ea81 in to a 1400 gen 1 stage 1 coupe that you only have aprox 11mm or less on each side of th heads / rocker covers before you hit in to the side rails.

I think a Ej15 will fit???

What I thought but every time i asked this... No one could give me a answer on....

I always thought the 1400 coupes body was smaller than the 1600 shaped ute/wagon etc.

Theres a 1600 in my GL 1400 coupe. going off memory theres about 15 or so mms each side

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IF you decide to go with an EA series FWD auto, subaruguru has a 2wd 3at from an 89 DL that still shifted great and was overall still a good working trans... Just in case.

 

Personally, I hate you (jk :banana:) because you have the car I want sooo badly, and I am about to build the perfect motor for it :banana:

 

I would go old school, but Hot Rod style. I love a restored, un modified rig, but I totally dig a well-thought out and well built hot rod even more, which is why I totally dig Kostamojen's FF-1 project :headbang:

 

Im not much for modern power, but if you can make it look right, in addition to run like a bat outa hell, then go for it. But if it would just turn out looking like a hack job with a rats nest of wiring under the hood, then I would have to give a big thumbs down. Its all in how you execute the idea onto the actual vehicle that will make it or break it.

 

Your car has a lot of great potential, and when its done it will turn heads anywhere it goes, and will be a pretty classy vehicle, and i cant wait to see it finished!

-Bill

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Is a EJ18 wider than a EJ15?

 

I know that if you where to fit in a Ea81 in to a 1400 gen 1 stage 1 coupe that you only have aprox 11mm or less on each side of th heads / rocker covers before you hit in to the side rails.

I think a Ej15 will fit???

What I thought but every time i asked this... No one could give me a answer on....

I always thought the 1400 coupes body was smaller than the 1600 shaped ute/wagon etc.

Theres a 1600 in my GL 1400 coupe. going off memory theres about 15 or so mms each side

All the 70's model GL/DL/etc.'s had the same shaped engine bay.

 

EJ15's are not availible in the US. I don't know what year they were made either, but IIRC, they were the same as the EJ20's and DOHC (or were they SOHC?) which made them rather wide.

 

The EJ18 is the same size case as the EJ22, so its best to find an EJ22 instead :) (or run EJ18 heads with an EJ22 shortblock for a "high compression" frankenstein)

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But if it would just turn out looking like a hack job with a rats nest of wiring under the hood, then I would have to give a big thumbs down. Its all in how you execute the idea onto the actual vehicle that will make it or break it.

You obviously haven't yet seen the Datsun he restored! :lol:

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You obviously haven't yet seen the Datsun he restored! :lol:

 

 

Thanks for the compliment. that resto was 6 years in the making with a lot of custom touches, especially in the engine compartment. It's an original engine out of a later model that I converted to an EFI/turbo setup. I built all the manifolds for the intake/exhaust from scratch. I also did a lot of upgrades on the brakes. All with no hacking! Webshots is down right now, so I'll put the link up later. I'll also link to pics I have of a 75' dodge Colt wagon I have that I swapped in a 92' Mighty Max 2.4 EFI engine into. No rats nests for me. I actually spent 2 days shortening the harness to make it clean! I am also currently restoring a 72' Corolla 2dr. wagon with a 98' Mitsu 6G72 V6 swap. (damn OBDII!) I need to head down to the area pick-n-pull to take some stuff back and will grab some measurement on an EJ to see if it's something I will consider. These newer motors usually clean up nicely when you don't need to worry about smog. :banana:

 

Mark

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well, you dont have to worry about smaog anyway, your car is a 1973, pre-smog man!

 

I think I did see that Datsun you did, and damn that was some fine work!

 

Well with that, I know you are the right guy to turn this rig into a show stopper!

 

Also, the EJ motors are too wide to fit in the Gen 1 engine bays without notching the framerails, which has been done by a few people who swapped EJ22s into Gen 1 Brats here on the board, so if you search Im sure you will find info on that as well.

 

I really cant wait to see what direction you take this project, its gonna be killer!

-Bill

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Also, the EJ motors are too wide to fit in the Gen 1 engine bays without notching the framerails, which has been done by a few people who swapped EJ22s into Gen 1 Brats here on the board, so if you search Im sure you will find info on that as well.

If you use stiff engine mounts, like CUSCO engine mounts or something along those lines, the early (90-94) EJ22's and EJ18's will fit between the rails without notching.

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Would that mean you would raise the engine hight up?

No, it means it wont move laterally, which means it won't hit the frame rails if theres even a slight amount of clearance still there (which from what i've seen of EJ22' installed in gen 1's, means you won't need to cut anything for it to work fine).

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Well, it looks like my choices have narrowed considerably! Spent a few hours checking out the various Subaru's in the boneyard and found this out,

 

-EJ22 is just about 1" too wide to fit in the car without a frame notch, and the location of the notch is right where one of the crossmember bolts sits. The exhaust might be an issue also. That and the fact there is no way an EJ automatic would fit without major tunnel surgery (along with a couple other issues) pretty much rules this one out. I was surprised to find out the EA82 is actually a little bit wider than the EJ, not that it was an option.

 

-3AT will not fit without tunnel surgery. It's about 2" or so too wide and quite a bit longer. I was kinda surprised about how big it is. Guess no automatic for me!

 

So, looks like it will be a pushrod motor of some sort with a stick. Now to narrow it down a little more

 

Is there a bolt in 5 speed option?

 

Has anyone actually installed the 1400 4 port heads onto a EA71 or EA81? It does not look like I can use 2 port heads due to the crossmember location. It will physically clear, but would most likely need to run under the crossmember, which I do not wish to do. Would look pretty cheesy with the pipes hanging low, IMO.

 

Who is a good source for performance machine work and parts such as cams/pistons? I will want to get as much RELIABLE/DRIVEABLE power out of this as I can. What is a good # to shoot for? Is 100 @ the crank acheiveable? I would envision a pretty much balanced/blueprinted bottom end with some sort of bigger cam, maybe upped compression if feasible, some nice port work on the heads, maybe with bigger valves, a custom exhaust header/system, and maybe a single Mikuni sidedraft on a custom manifold. (just something a little different than your run of the mill 32/36 :)) I would obviously like to start with the most displacement I can, but it seem from searching the EA81 won't accept the 4 port heads, so I am probably "stuck" with an EA71. Thanks for the replies so far and keep them coming!

 

Mark

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Is there a bolt in 5 speed option?

The earlyer 5 speed will fit. But apparntly the later ea71 5 speed for a 1979-1984 leone can fit but needs some mod somewhere?

 

Has anyone actually installed the 1400 4 port heads onto a EA71 or EA81? It does not look like I can use 2 port heads due to the crossmember location. It will physically clear, but would most likely need to run under the crossmember, which I do not wish to do. Would look pretty cheesy with the pipes hanging low, IMO.

I beleve a guy on here from oz did that in the 1970s/80s. he has talked about it. ea71 he used but ea81 different etc. cant remember exact details

 

 

Mark

 

:)

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Is there a bolt in 5 speed option?

 

Has anyone actually installed the 1400 4 port heads onto a EA71 or EA81? It does not look like I can use 2 port heads due to the crossmember location. It will physically clear, but would most likely need to run under the crossmember, which I do not wish to do. Would look pretty cheesy with the pipes hanging low, IMO.

 

Who is a good source for performance machine work and parts such as cams/pistons? I will want to get as much RELIABLE/DRIVEABLE power out of this as I can. What is a good # to shoot for? Is 100 @ the crank acheiveable? I would envision a pretty much balanced/blueprinted bottom end with some sort of bigger cam, maybe upped compression if feasible, some nice port work on the heads, maybe with bigger valves, a custom exhaust header/system, and maybe a single Mikuni sidedraft on a custom manifold. (just something a little different than your run of the mill 32/36 :)) I would obviously like to start with the most displacement I can, but it seem from searching the EA81 won't accept the 4 port heads, so I am probably "stuck" with an EA71. Thanks for the replies so far and keep them coming!

 

Mark

Yes, there is a 5-speed FWD option!!! There were a few 5-speed FWD transmissions from 75 on I believe, in specific models though. They even had some with the EA81's. Its basically the same "case" but they added the 5th gear in the rear housing outside of the main case.

 

Yes, people have fit the 4-port EA63 heads to an EA71 shortblock. Here is a photo of one for example, owned by another member here:

 

100_4118.jpg

Subarueng1-1.jpg

 

When dissected, it was discovered that while this motor was bad (due to water) it DID have upgraded valves AND pistons to go along with the apparently upgrade springs and the custom head work to fit the dual barrel carbs on each side:

 

100_4141.jpg

100_4137.jpg

 

However, most of the work done on that engine was apparently done a LONG time ago, so sourcing those parts will be next to impossible now...

 

For reference, my goal with my FF-1 is to run some 1400 4-port heads with the EA71 shortblock for reliablity PLUS the aftermarket Weber manifold I lucked out and found for sale in Japan and now own:

 

webermanifold1.jpg

 

I haven't decided how much other work I'll do with the setup, but I will have the cam reground probably by Delta-cam and have the heads ported at the very least (along with a shortblock rebuilt, unless I find an already re-built block for sale, but it will probably have to be a junkyard block that i'll have to rebuild).

 

If you do decide to go that route too, maybe we should combine our efforts and have the work done at the same place at the same time? LOL!

 

HOWEVER, you have quite a few other options too...

 

An EA81 with a corresponding 5-speed transmission would be an upgrade. PLUS you can do whatever you want with the internals and maybe run a dual-carb setup (the dual-carb setups were on the "sport" models in Japan and elsewhere, not sold in the US):

 

3dually-4.jpg

 

You also have the option to go with a TURBO EA81 if you can find one:

 

willyslump.jpg

(not sure if that is an EA81 or EA82, but you get the idea)

 

There have also been a few odd-ball setups that i've seen over the years that might peak your interest...

 

e9_1-1.jpg

91_1.jpg

DSC00905.jpg

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I think I'm wearing out the search! :lol: nOOb questions upcoming :eek:

 

So, if the heads will retrofit to the EA71, why won't they fit the EA81? Isn't the EA81 just a stroked version of the EA71, or was the motor somehow revised? What about the part I saw about having to weld up some water passages? Kostamojen, those are some awesome pics. Someone put an awful lot of work into those 4 port heads! The supercharger is cool too. The bottom pic of the sidedraft is kinda what I'm thinking of doing. Probably a 40mm w/ 34 chokes. The EA81 complete motor probably is not an option due to the exhaust port location. I don't want to run it under the crossmember. I'm down for going together on stuff like pistons/OS valves/porting. I'm not necessarily planning to build an engine right away but let's keep in touch on that. I'm going to keep my eyes open for a 5 speed now.

 

Mark

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Good n00b questions actually.

 

There are technically TWO types of EA71's... Those built before 1980, and those built after 1980.

 

The ones built before 1980 resemble the other 70's blocks, and have an EXTERNAL coolant passage on top of the motor which connects to the water pump, you can see it in this photo:

 

P1010019.jpg

 

The post-1980 EA71's are essentially EA81's but with different pistons and perhaps a narrower case (not sure about this exactly) but either way, the water passage is INTERNAL and you can see how the waterpump is situated in this photo:

 

249153915_2e8d3d3857.jpg?v=0

 

The post-1980 or Gen 2 EA71, shares nothing really block/head wise with the previous EA71 minus the name and displacement.

 

So in order to use the 1400 heads, you need the earlier EA71 shortblock with the external coolant passage.

 

As for the "welding" of passages, I don't think that is the case if you use the correct shortblock. As you can see in those photos of that split case on that "modified" motor, there were no welded passages and it did operate as a race motor at some point. Having the two headgaskets side-by-side would be the best method to see how these fit (which reminds me, I need to buy some EA71 headgaskets to check this... Already have the EA63's!)

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Im really glad were all in the same boat here, you guys are talking about building the motor I am preparing to build right now!

 

I have been looking over the motors and the various parts I have, and what I see is that the 1400 heads appear that they WILL INDEED fit the post 1980 EA71, although a modified head gasket may be needed (think 2.5 with 2.2 heads, same deal) The Post-'80 is 1" narrower than the EA81, and is exactly the same width as the 1400 and the pre-80 EA71.

 

The Post-and-Pre-80 EA71 heads do interchange.

 

I also have a EA71 Dual Carb manifold :slobber: that is going on my motor

 

Turns out the JDM manifold is about 3/16" narrower than the USDM 1400 and 1600 manifolds :-\ so there will be some machining to make it fit

 

I also have a pair of JDM flat top pistons marked 25 on the surface, not sure what this means. I posted some random questions in the historic section, I really think we should all work together and build a set of KILLER EA71/63 Hybrids, Im shootin for 120HP if its at all possible.

 

I have a lot of parts to compare and take measurements, if you guys need something let me know.

 

Oh Kosta, Im uber jealous of that Weber manifold :slobber::slobber::slobber:

 

-Bill

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Now there you go trying to tempt me with that turbo motor! Don't think the thought didn't cross my mind! :grin: So it would seem the best course of action would be the early EA71 with the 1400 4 port heads and reground EA63 cam. Mods to be possible high compression pistons (if the 1400 head swap doesn't raise it), larger valves (cost dependent) with some port work, lightened flywheel, custom stainless headers and a sidedraft weber. Sounds like a workable plan! Just need to find an EA71 now! :lol:

 

BTW, what would the best header design be? I would think you would want all primaries to be equal length (stock is short/long) with a relatively short length under 36" prefferable. I would guess it would need be of a "tri Y" variety as a 4 into 1 design would probably have undesireably long primaries for good top end power. I would think 1 1/2" primaries into 1 3/4" 2 into 1 collectors for the left/right banks, then 1 3/4" into 2" collector for the connection to the exhaust system. That should be more than sufficient for the power this combo will produce. It's speculation at this point but sounds good. :-\

 

Mark

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I myself am thinking of a long-tube header setup, with 2-into-1 from each head, then an x-pipe and full dual exhaust with glasspacks or flowmasters that exit just before the reare wheels. As for pipe size, I guess that partially depends on how much the exhaust ports get opened up, but if they are 1 1/2" stock thats prolly the best size to start with. Like I stated, i have all the parts I can measure and get dimensions, so if you need something let me know.

 

-Bill

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Im really glad were all in the same boat here, you guys are talking about building the motor I am preparing to build right now!

 

I have been looking over the motors and the various parts I have, and what I see is that the 1400 heads appear that they WILL INDEED fit the post 1980 EA71, although a modified head gasket may be needed (think 2.5 with 2.2 heads, same deal) The Post-'80 is 1" narrower than the EA81, and is exactly the same width as the 1400 and the pre-80 EA71.

 

The Post-and-Pre-80 EA71 heads do interchange.

 

I also have a EA71 Dual Carb manifold :slobber: that is going on my motor

 

Turns out the JDM manifold is about 3/16" narrower than the USDM 1400 and 1600 manifolds :-\ so there will be some machining to make it fit

 

I also have a pair of JDM flat top pistons marked 25 on the surface, not sure what this means. I posted some random questions in the historic section, I really think we should all work together and build a set of KILLER EA71/63 Hybrids, Im shootin for 120HP if its at all possible.

 

I have a lot of parts to compare and take measurements, if you guys need something let me know.

 

Oh Kosta, Im uber jealous of that Weber manifold :slobber::slobber::slobber:

 

-Bill

 

Wow, this is moving fast. barely submit a reply and there is more info! I love it. Now the question is, if supposedly the early and late EA71 heads interchange, and the late EA71 and EA81 are the same, why can't the EA63 heads fit the EA81? An extra 200cc's is an extra 200cc's! The head gasket might not be that big a deal either. I'm pretty sure there are places that can punch out some copper ones, in whatever thickness is specified, which may help bump the compression using off the shelf pistons. (MLS would be killer, but impractable due to cost)

 

Mark

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